Bizima Karaha, speaking from the rebels' eastern stronghold of Goma, said he had no details, but warned that Angolan involvement would complicate the crisis and that rebels would strike back.
Zimbabwe already had deployed troops to help Congolese President Laurent Kabila ward off rebel advances on the capital, Kinshasa.
The insurgents, who accuse Kabila of power-grabbing, tribalism and mismanagement of his vast African nation, drew within 18 miles of the capital on Saturday.
"We are calling upon the people of Congo to hold the aggression," Karaha said. "Angolans must come to their senses and remove forces from Congo immediately."
Angola's entry into Congo's civil war has made chances of a negotiated settlement "almost impossible," he added.
Written by Hrvoje Hranjski